“We ask that the media respect her privacy as well as those of her family and friends at this time.”

Her ex-husband Federline is said to be worried about her.

“Kevin is concerned for Britney and his children,” a friend told People.

“Of course he’s concerned about her. He loves her. He’s always loved her – even after she started divorce proceedings.”

The pair have two sons together, Sean Preston, one, and five-month-old Jayden James.

The singer is said to have spent just 24 hours in a facility last week before shocking fans and prompting fears over her health by shaving off her own hair in full view of photographers.

The 25-year-old mother-of-two reportedly visited Eric Clapton’s Crossroads Centre in Antigua for just one day last week.

Entertainment website TMZ.com said that according to sources Spears was at a Los Angeles in-patient facility.

The fallen star’s wild weekend began on Friday night when she turned up at Esther’s Hair Salon in Tarzana, California, and demanded that owner Esther Tognozzi shave her head.

When the hairdresser refused, Spears grabbed the clippers and did the job herself, as shocked passers by and photographers watched through the windows.

The star then moved on and got two new tattoos of pairs of pink lips, while listening to a Janis Joplin CD.

Unconfirmed reports claimed she later turned up at the Cedars Sinai Medical Centre in Beverly Hills wearing a dark wig.

But apparently she left soon after arriving.

The shocking buzzcut prompted suggestions the pop princess was on the verge of some kind of breakdown.

By Sunday however she was up and about and sporting a cheap-looking platinum blonde bobbed wig.

Spears’s return to rehab was said to be at the urging of her family, including her mother Lynne.

Fans have been increasingly concerned for her ever since she filed for divorce from wannabe rapper Kevin Federline in November.

The pair are battling for custody of their two infant sons.

At first it seemed Spears was getting her life back on track after the much criticised marriage, but then she horrified followers by repeatedly being photographed flashing her crotch on wild nights out with heiress Paris Hilton.

In the New Year she tried to make amends, admitting her behaviour had been “been far from perfect” and promising she was now “more mature”.

But the resolution was to be shortlived.

Last week Spears surprised clubgoers in New York when she partied with a group of lapdancers, slipping out of her skimpy red dress to try on their bikinis and fishnets.

Earlier Britney Spears had a heart-to-heart with her father following her head-shaving antics.

The newly bald star, sporting an unrealistic platinum blonde bobbed wig, was reportedly engrossed in conversation with Jamie Spears at a New Orleans-themed restaurant in California on Sunday.

“Britney and her dad ate in a private VIP section,” a restaurant worker told the New York Daily News.

“She was in such an intense conversation with her dad that no one wanted to bother her.”